One of the most common complaints about ferrets fighting is when a new ferret is introduced to the household. As ferrets get older, they seem to become less and less tolerant of newcomers. Any new ferret is considered an interloper who is trespassing on private territory! The typical reaction is an exclusionary fight. Unfortunately, newcomers are at a disadvantage because they aren’t familiar enough with the territory to know where to run, or they are outnumbered, or they are smaller (as in the case of kits being introduced to adult ferrets).